///////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//                                          MusicBrainz Import helper functions
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////

/*
 * How to use this module?
 *
 * - First build a release object (see expected format below) that you'll fill in from source of data
 * - Call as follows, e.g.:
 *     var parameters = MBImport.buildFormParameters(parsedRelease, optionalEditNote);
 * - Then build the HTML that you'll inject into source site page:
 *     var formHtml = MBImport.buildFormHTML(parameters);
 * - Addinionally, you can inject a search link to verify that the release is not already known by MusicBrainz:
 *     var linkHtml = MBImport.buildSearchLink(parsedRelease);
 *
 * Expected format of release object:
 *
 *     release = {
 *         title,
 *         artist_credit,
 *         type,
 *         status,
 *         secondary_types,
 *         language,
 *         script,
 *         packaging,
 *         country,
 *         year,
 *         month,
 *         day,
 *         labels = [ { name, mbid, catno }, ... ],
 *         barcode,
 *         comment,
 *         annotation,
 *         urls = [ {url, link_type }, ... ],
 *         discs = [
 *             {
 *                 title,
 *                 format,
 *                 tracks = [
 *                     { number, title, duration, artist_credit },
 *                     ...
 *                 ]
 *             },
 *             ...
 *         ],
 *     }
 *
 *     where 'artist_credit' has the following format:
 *
 *     artist_credit = [
 *         {
 *             credited_name,
 *             artist_name,
 *             artist_mbid,
 *             joinphrase
 *         },
 *         ...
 *     ]
 *
 */

var MBImport = (function () {
    // --------------------------------------- publics ----------------------------------------- //

    let special_artists = {
        various_artists: {
            name: 'Various Artists',
            mbid: '89ad4ac3-39f7-470e-963a-56509c546377',
        },
        unknown: {
            name: '[unknown]',
            mbid: '125ec42a-7229-4250-afc5-e057484327fe',
        },
    };

    let url_types = {
        purchase_for_download: 74,
        download_for_free: 75,
        discogs: 76,
        purchase_for_mail_order: 79,
        other_databases: 82,
        stream_for_free: 85,
        license: 301,
    };

    function fnSpecialArtist(key, ac) {
        let credited_name = '';
        let joinphrase = '';
        if (typeof ac !== 'undefined') {
            joinphrase = ac.joinphrase;
        }
        return {
            artist_name: special_artists[key].name,
            credited_name: credited_name,
            joinphrase: joinphrase,
            mbid: special_artists[key].mbid,
        };
    }

    // compute HTML of search link
    function fnBuildSearchLink(release) {
        let parameters = searchParams(release);
        let url_params = [];
        parameters.forEach(function (parameter) {
            let value = `${parameter.value}`;
            url_params.push(encodeURI(`${parameter.name}=${value}`));
        });
        return `<a class="musicbrainz_import" href="//musicbrainz.org/search?${url_params.join('&')}">Search in MusicBrainz</a>`;
    }

    // compute HTML of search button
    function fnBuildSearchButton(release) {
        let parameters = searchParams(release);
        let html = `<form class="musicbrainz_import musicbrainz_import_search" action="//musicbrainz.org/search" method="get" target="_blank" accept-charset="UTF-8" charset="${document.characterSet}">`;
        parameters.forEach(function (parameter) {
            let value = `${parameter.value}`;
            html += `<input type='hidden' value='${value.replace(/'/g, '&apos;')}' name='${parameter.name}'/>`;
        });
        html += '<button type="submit" title="Search for this release in MusicBrainz (open a new tab)"><span>Search in MB</span></button>';
        html += '</form>';
        return html;
    }

    function fnSearchUrlFor(type, what) {
        type = type.replace('-', '_');

        let params = [`query=${luceneEscape(what)}`, `type=${type}`, 'indexed=1'];
        return `//musicbrainz.org/search?${params.join('&')}`;
    }

    // compute HTML of import form
    function fnBuildFormHTML(parameters) {
        // Build form
        let innerHTML = `<form class="musicbrainz_import musicbrainz_import_add" action="//musicbrainz.org/release/add" method="post" target="_blank" accept-charset="UTF-8" charset="${document.characterSet}">`;
        parameters.forEach(function (parameter) {
            let value = `${parameter.value}`;
            innerHTML += `<input type='hidden' value='${value.replace(/'/g, '&apos;')}' name='${parameter.name}'/>`;
        });

        innerHTML +=
            '<button type="submit" title="Import this release into MusicBrainz (open a new tab)"><img src="//musicbrainz.org/favicon.ico" /><span>Import into MB</span></button>';
        innerHTML += '</form>';

        return innerHTML;
    }

    // build form POST parameters that MB is waiting
    function fnBuildFormParameters(release, edit_note) {
        // Form parameters
        let parameters = new Array();
        appendParameter(parameters, 'name', release.title);

        // Release Artist credits
        buildArtistCreditsFormParameters(parameters, '', release.artist_credit);

        if (release['secondary_types']) {
            for (let i = 0; i < release.secondary_types.length; i++) {
                appendParameter(parameters, 'type', release.secondary_types[i]);
            }
        }
        appendParameter(parameters, 'status', release.status);
        appendParameter(parameters, 'language', release.language);
        appendParameter(parameters, 'script', release.script);
        appendParameter(parameters, 'packaging', release.packaging);

        // ReleaseGroup
        appendParameter(parameters, 'release_group', release.release_group_mbid);

        // Date + country
        appendParameter(parameters, 'country', release.country);
        if (!isNaN(release.year) && release.year != 0) {
            appendParameter(parameters, 'date.year', release.year);
        }
        if (!isNaN(release.month) && release.month != 0) {
            appendParameter(parameters, 'date.month', release.month);
        }
        if (!isNaN(release.day) && release.day != 0) {
            appendParameter(parameters, 'date.day', release.day);
        }

        // Barcode
        appendParameter(parameters, 'barcode', release.barcode);

        // Disambiguation comment
        appendParameter(parameters, 'comment', release.comment);

        // Annotation
        appendParameter(parameters, 'annotation', release.annotation);

        // Label + catnos
        for (let i = 0; i < release.labels.length; i++) {
            let label = release.labels[i];
            appendParameter(parameters, `labels.${i}.name`, label.name);
            appendParameter(parameters, `labels.${i}.mbid`, label.mbid);
            if (label.catno != 'none') {
                appendParameter(parameters, `labels.${i}.catalog_number`, label.catno);
            }
        }

        // URLs
        for (let i = 0; i < release.urls.length; i++) {
            let url = release.urls[i];
            appendParameter(parameters, `urls.${i}.url`, url.url);
            appendParameter(parameters, `urls.${i}.link_type`, url.link_type);
        }

        // Mediums
        let total_tracks = 0;
        let total_tracks_with_duration = 0;
        let total_duration = 0;
        for (let i = 0; i < release.discs.length; i++) {
            let disc = release.discs[i];
            appendParameter(parameters, `mediums.${i}.format`, disc.format);
            appendParameter(parameters, `mediums.${i}.name`, disc.title);

            // Tracks
            for (let j = 0; j < disc.tracks.length; j++) {
                let track = disc.tracks[j];
                total_tracks++;
                appendParameter(parameters, `mediums.${i}.track.${j}.number`, track.number);
                appendParameter(parameters, `mediums.${i}.track.${j}.name`, track.title);
                let tracklength = '?:??';
                let duration_ms = hmsToMilliSeconds(track.duration);
                if (!isNaN(duration_ms)) {
                    tracklength = duration_ms;
                    total_tracks_with_duration++;
                    total_duration += duration_ms;
                }
                appendParameter(parameters, `mediums.${i}.track.${j}.length`, tracklength);
                appendParameter(parameters, `mediums.${i}.track.${j}.recording`, track.recording);
                buildArtistCreditsFormParameters(parameters, `mediums.${i}.track.${j}.`, track.artist_credit);
            }
        }

        // Guess release type if not given
        if (!release.type && release.title && total_tracks == total_tracks_with_duration) {
            release.type = fnGuessReleaseType(release.title, total_tracks, total_duration);
        }
        appendParameter(parameters, 'type', release.type);

        // Add Edit note parameter
        appendParameter(parameters, 'edit_note', edit_note);

        return parameters;
    }

    // Convert a list of artists to a list of artist credits with joinphrases
    function fnArtistCredits(artists_list) {
        let artists = artists_list.map(function (item) {
            return { artist_name: item };
        });
        if (artists.length > 2) {
            let last = artists.pop();
            last.joinphrase = '';
            let prev = artists.pop();
            prev.joinphrase = ' & ';
            for (let i = 0; i < artists.length; i++) {
                artists[i].joinphrase = ', ';
            }
            artists.push(prev);
            artists.push(last);
        } else if (artists.length == 2) {
            artists[0].joinphrase = ' & ';
        }
        let credits = [];
        // re-split artists if featuring or vs
        artists.map(function (item) {
            let c = item.artist_name.replace(/\s*\b(?:feat\.?|ft\.?|featuring)\s+/gi, ' feat. ');
            c = c.replace(/\s*\(( feat. )([^\)]+)\)/g, '$1$2');
            c = c.replace(/\s*\b(?:versus|vs\.?)\s+/gi, ' vs. ');
            c = c.replace(/\s+/g, ' ');
            let splitted = c.split(/( feat\. | vs\. )/);
            if (splitted.length == 1) {
                credits.push(item); // nothing to split
            } else {
                let new_items = [];
                let n = 0;
                for (let i = 0; i < splitted.length; i++) {
                    if (n && (splitted[i] == ' feat. ' || splitted[i] == ' vs. ')) {
                        new_items[n - 1].joinphrase = splitted[i];
                    } else {
                        new_items[n++] = {
                            artist_name: splitted[i].trim(),
                            joinphrase: '',
                        };
                    }
                }
                new_items[n - 1].joinphrase = item.joinphrase;
                new_items.map(function (newit) {
                    credits.push(newit);
                });
            }
        });
        return credits;
    }

    // Try to guess release type using number of tracks, title and total duration (in millisecs)
    function fnGuessReleaseType(title, num_tracks, duration_ms) {
        if (num_tracks < 1) return '';
        let has_single = !!title.match(/\bsingle\b/i);
        let has_EP = !!title.match(/\bEP\b/i);
        if (has_single && has_EP) {
            has_single = false;
            has_EP = false;
        }
        let perhaps_single = (has_single && num_tracks <= 4) || num_tracks <= 2;
        let perhaps_EP = has_EP || (num_tracks > 2 && num_tracks <= 6);
        let perhaps_album = num_tracks > 8;
        if (isNaN(duration_ms)) {
            // no duration, try to guess with title and number of tracks
            if (perhaps_single && !perhaps_EP && !perhaps_album) return 'single';
            if (!perhaps_single && perhaps_EP && !perhaps_album) return 'EP';
            if (!perhaps_single && !perhaps_EP && perhaps_album) return 'album';
            return '';
        }
        let duration_mn = duration_ms / (60 * 1000);
        if (perhaps_single && duration_mn >= 1 && duration_mn < 7) return 'single';
        if (perhaps_EP && duration_mn > 7 && duration_mn <= 30) return 'EP';
        if (perhaps_album && duration_mn > 30) return 'album';
        return '';
    }

    // convert HH:MM:SS or MM:SS to milliseconds
    function hmsToMilliSeconds(str) {
        /*  eslint-disable-next-line use-isnan */
        if (typeof str == 'undefined' || str === null || str === NaN || str === '') return NaN;
        if (typeof str == 'number') return str;
        let t = str.split(':');
        let s = 0;
        let m = 1;
        while (t.length > 0) {
            s += m * parseInt(t.pop(), 10);
            m *= 60;
        }
        return s * 1000;
    }

    // convert ISO8601 duration (limited to hours/minutes/seconds) to milliseconds
    // format looks like PT1H45M5.789S (note: floats can be used)
    // https://en.wikipedia.org/wiki/ISO_8601#Durations
    function fnISO8601toMilliSeconds(str) {
        let regex = /^PT(?:(\d*\.?\d*)H)?(?:(\d*\.?\d*)M)?(?:(\d*\.?\d*)S)?$/,
            m = str.replace(',', '.').match(regex);
        if (!m) return NaN;
        return (3600 * parseFloat(m[1] || 0) + 60 * parseFloat(m[2] || 0) + parseFloat(m[3] || 0)) * 1000;
    }

    function fnMakeEditNote(release_url, importer_name, format, home = 'https://github.com/murdos/musicbrainz-userscripts') {
        return `Imported from ${release_url}${format ? ` (${format})` : ''} using ${importer_name} import script from ${home}`;
    }

    // --------------------------------------- privates ----------------------------------------- //

    function appendParameter(parameters, paramName, paramValue) {
        if (!paramValue) return;
        parameters.push({ name: paramName, value: paramValue });
    }

    function luceneEscape(text) {
        let newtext = text.replace(/[-[\]{}()*+?~:\\^!"\/]/g, '\\$&');
        return newtext.replace('&&', '&&').replace('||', '||');
    }

    function buildArtistCreditsFormParameters(parameters, paramPrefix, artist_credit) {
        if (!artist_credit) return;
        for (let i = 0; i < artist_credit.length; i++) {
            let ac = artist_credit[i];
            appendParameter(parameters, `${paramPrefix}artist_credit.names.${i}.name`, ac.credited_name);
            appendParameter(parameters, `${paramPrefix}artist_credit.names.${i}.artist.name`, ac.artist_name);
            appendParameter(parameters, `${paramPrefix}artist_credit.names.${i}.mbid`, ac.mbid);
            if (typeof ac.joinphrase != 'undefined' && ac.joinphrase != '') {
                appendParameter(parameters, `${paramPrefix}artist_credit.names.${i}.join_phrase`, ac.joinphrase);
            }
        }
    }

    function searchParams(release) {
        let params = [];

        const totaltracks = release.discs.reduce((acc, { tracks }) => acc + tracks.length, 0);
        let release_artist = '';
        for (let i = 0; i < release.artist_credit.length; i++) {
            let ac = release.artist_credit[i];
            release_artist += ac.artist_name;
            if (typeof ac.joinphrase != 'undefined' && ac.joinphrase != '') {
                release_artist += ac.joinphrase;
            } else {
                if (i != release.artist_credit.length - 1) release_artist += ', ';
            }
        }

        let query =
            `artist:(${luceneEscape(release_artist)})` +
            ` release:(${luceneEscape(release.title)})` +
            ` tracks:(${totaltracks})${release.country ? ` country:${release.country}` : ''}`;

        appendParameter(params, 'query', query);
        appendParameter(params, 'type', 'release');
        appendParameter(params, 'advanced', '1');
        return params;
    }

    // ---------------------------------- expose publics here ------------------------------------ //

    return {
        buildSearchLink: fnBuildSearchLink,
        buildSearchButton: fnBuildSearchButton,
        buildFormHTML: fnBuildFormHTML,
        buildFormParameters: fnBuildFormParameters,
        makeArtistCredits: fnArtistCredits,
        guessReleaseType: fnGuessReleaseType,
        hmsToMilliSeconds: hmsToMilliSeconds,
        ISO8601toMilliSeconds: fnISO8601toMilliSeconds,
        makeEditNote: fnMakeEditNote,
        searchUrlFor: fnSearchUrlFor,
        URL_TYPES: url_types,
        SPECIAL_ARTISTS: special_artists,
        specialArtist: fnSpecialArtist,
    };
})();